1. Field of the Invention
The present invention relates to a magnetic recording disc-jacket assembly wherein a cleaning liner made of fibrous material such as a non-woven fabric is provided.
2. Related Art
In a magnetic recording disc-jacket assembly of this type, it is common to provide a cleaning liner made of soft and flexible fibrous material such as non-woven fabric for the protection and cleaning of a magnetic recording disc accommodated in the jacket. Such a cleaning liner is spot heat-bonded to the inner surface of the jacket at dotted or linear heat-bonding portions. The cleaning liner of this nature is likely to be frayed along cut edges formed by punching out apertures such as a central window and a head window. In order to prevent the fraying of the fibrous material along such cut edges, it has been proposed to form the above-mentioned heat-bonding portions more densely along the edge portions (see e.g. U.S. Pat. No. 4,392,170 or Japanese Unexamined Patent Publication No. 58510/1977). However, in such a proposal, when the liner is heat-bonded to the inner surface of the jacket sheet material, a greater quantity of heat is required to be applied to the high density heat-bonding portions, whereby there have been problems such as a deformation of the jacket sheet material or formation of sealing marks on the outersurface of the jacket, which impair the outer appearance.